Barcode readers and other such portable devices are often moved from one environment to another to facilitate data entry in a variety of locations. For example, it is not uncommon to use a barcode reader in a standard room-temperature environment (e.g., within a commercial shopping space), then use that same barcode reader in a warehouse region or refrigerated area (e.g., a walk-in freezer). Such drastic change of environments is often experienced, for example, in the food service industry.
When a barcode reader is moved from one environment to another, condensation can build up on internal or external surfaces. That is, if the temperature of an optical component drops below the effective dew point of the local environment, small droplets of water can form on the cold surface of that component. When such condensation or “fogging” occurs on optical components, windows, or any part within the optical path, distortion may occur, causing the barcode reader to incorrectly scan barcodes or become largely unusable.
Certain prior art barcode systems incorporate a heated window or a heated holster to prevent condensation. Such systems are costly, take up significant space, and require substantial power. Other prior art systems have incorporated desiccants within the barcode reader housing; however, desiccants are unsatisfactory in that they must be replaced when fully saturated.
Accordingly, it is desirable to provide an efficient barcode reading device that can accommodate changes in environment without significant formation of condensation.